Calculating the unreachable pose on UR robot

edit

Hello guys, I am trying to find out the unreachable pose and some singularity points based on six-axis robot, just like UR robot. In fact, when i am given a coordinate value of the end-effector of a UR robot from a vision system, i am not sure if this position is reachable for the robot. So i want to pre-calculate and prevent the robot moving to a unreachable point. Maybe Moveit can give me this abnormal area of a robot. Or do you guys know how to predict occurrence of these situations in Moveit. Thanks a lot.